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-------------------------------------------------------------- This story was printed from ZDNet Australia. --------------------------------------------------------------
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Networking for smarts By Kire Terzievski, Technology & Business magazine May 20, 2005 URL: http://www.zdnet.com.au/reviews/software/internet/soa/Networking-for-smarts/0,139023437,139192360,00.htm
 
In this product review, we look at tools that can monitor network performance.
The tools tested can do analysis, migration, monitoring, security, and testing. What's most impressive is that some of these tools can help you see problems immediately, taking the guesswork out of problem solving network issues. Some even use Expert Analysis to make a recommendation on how you should rectify your network problem. Packet capture. Some of the software tools allow you to capture packets across your network then decode them for you. These tools can almost make perfect hacking tools since you will be able to sniff all the traffic on your network. Expert systems. Expert systems on the other hand can offer real-time recommendations to potential network problems. The expert system can not only spot network anomalies but it can eliminate the guess work and give you the root cause of the problem. Traffic generation. It is also possible to create different traffic loads to assist you with stress testing your network. This may be an area of interest for someone who would like to investigate how the network will stand up to increased traffic and more end users.
Remote analysis. Remote monitoring can make it easy and economical to extend your knowledge and expertise across your network. With some of these tools you can monitor distant sites directly from your desktop so you can zero in on problems. A worthy thing to find out is how many remote sessions you can run at any one time.
Packet shaping and bandwidth compression devices allow you to shape and compress data so you can lower your bandwidth costs. They also increase your network performance. Networking vendors like Cisco and Nortel offer routers with queuing capabilities and for someone who requires simple queuing or prioritisation, this may be all they need for basic shaping. However, when there is a need to distinguish specific applications within the traffic, routers will not be able to do much for you. This is where dedicated packet shapers come into it as they can offer better policy enforcement than traditional network switches and routers. Packet shapers primarily classify network traffic into categories based on applications, protocols, subnets, and URLs. They can match a user's IP address to specific applications like SAP or Kazaa. They also allow you to analyse clients and servers with the slowest performance, as well as users who generate or receive the most network traffic. Typical data that can be attained from a packet shaper include the type of data being sent and received, the percentage of bandwidth wasted by re-transmission, the number of dropped packets in correlation with the matching application and server, and how much bandwidth goes to Web browsing, music, downloads, and e-mail. There are many ways you can shape traffic; one way is capping traffic. For example, you can reserve a minimum of 20 percent of the WAN link for e-mail and set the virtual link to exceed the minimum if bandwidth is available but cap it at 50 percent of the link. You can set all sorts of minimum and maximum bandwidth rates for specific applications. This way you can ensure a smooth and even flow rate that will maximise your throughput.
Then there are compression devices -- these will allow you to compress data, which can accelerate your traffic and minimise your network bandwidth costs, as you will be transferring less data.
During the first transmission a bandwidth compression device will significantly reduce data and after that it starts matching traffic patterns to even further reduce the size of the data. The figures used here are quite impressive to say the least, however the results you get from the device will mainly depend on the type of data you are compressing. For example, if you were to transfer executable files over the network you probably won't be reducing the file sizes by much since the files are already packed very tightly, the same can be said about Zip or MP3 files. If you are interested in reading some white papers on MSR you will find plenty on the Peribit Web site.
Observer by Network Instruments is a network protocol analyser, monitor, and troubleshooting tool. Observer isn't limited to only monitoring wired networks, it can also monitor your wireless network to provide you with an overall network monitoring solution. The Wireless Site Survey can see a, b, and g devices. What's really impressive is that it can show you what the link quality is like, the encryption status, and other information like the up time of the device and when the device was first and last seen on a per-device basis. The Observer package has three levels of licensing; the standalone Observer which is what we looked at, the Expert Observer which enables you to pinpoint network problems through expert analysis, and the Observer Suite which includes the Expert Observer plus additional network management and analysis solutions. The standalone Observer or console includes a local probe that makes the local network visible to it. In order to monitor multiple networks from a single console you have to install what is called a probe. These probes collect and report network traffic and report it back to the console. The installation of the Observer was straightforward. There are only a few screens to get through and you're done, it really doesn't get much easier. Then the quickest way to collect information from your network is to run Discover Network Names function. All you have to do is specify your network range of addresses then what Observer does is resolve DNS names and IP addresses to give you a list of all your network devices. You can then select the Top Talkers, which has to be one of the easiest functions to use. It allows you to see which devices are sending and receiving the most traffic on the network. Router's can be examined for bottlenecks by using the Router Observer while Internet usage can be monitored by using the Internet Observer. The monitor here can determine which Internet protocols are in use and which Internet sites users are visiting.
In real time, it can also display the amount of bandwidth being utilised and how your network has been trending or performing over time.
AppManager is a systems management tool that lets you manage your applications and infrastructure. Its main aim is to increase network availability and manage service levels. This tool is designed to monitor the health of all your critical servers in Windows and Unix environments. More so it allows you to create specific monitoring policies, which will alert you if your critical server's aren't performing the way they should. Installing AppManager can be quite a lengthy process to say the least. There are so many components to install and you may find it a bit daunting trying to understand how everything ties in together. AppManager works on multi-tier architecture. The main components are the Console, which you use to configure and control the execution of your monitors -- or what NetIQ know as Knowledge Scripts. The second tier comprises of the Repository, which is the SQL Database that serves as the data repository. The third tier is the Management Server, which is the service daemon the agents on Windows and Unix clients use to communicate with the Repository. The fourth tier is the Intelligent Agent -- these are agents that have to be distributed on every server you want to monitor. They receive requests from the Management Server to run and stop monitoring jobs. AppManager has a pre-installation feature which checks to see whether the components you are about to install pass the system requirements. We found we had to go back a few times to fix up the errors that came up with items not being preinstalled. Once we got passed the pre-installation, we ran the installation. Again, it wasn't an easy process as there are a number of screens you have to carefully read and hope you didn't make any mistakes anywhere. In all, the installation took us about an hour, which is a lot more than we are used to.
Included in AppManager are more than 400 of these predefined Knowledge Scripts. You can also create your own monitoring scripts. Some of the out-of-the-box monitors you can use include:
With all this data you are going to want to be able to create reports. AppManager has some very powerful charting capabilities.For example, with its 3D charting you can do real-time rotation as well as have the ability to export charts to Microsoft Word and Excel.
Lightspeed Systems have a bandwidth management tool that can guarantee the bandwidth for your critical applications. It does this by blocking or limiting the bandwidth that is used by non-priority applications. This is similar to what packet shapers do. This tool can monitor everyone's activities from:
Unfortunately we didn't get a chance to test this product because of our tight deadline for this month. If you're interested in testing this product yourself be warned of the system requirements.
We evaluated each tool on a P4 2.6GHz machine with 512MB of RAM running Windows 2000 Advanced Server. We had 30 PCs connected to our network across four switches and single router to the outside world. We tested each tool in these areas: Interoperability: We looked at the network topologies it supports (for example Ethernet 10/100/1000 & Wireless a, b and g networks. Futureproofing: What upgrade features are available? ROI: What do you get for your money? Service: What service and support is available. Sample scenario This company wants to measure the performance and application responsiveness of its Exchange and Apache Web Servers from a user's point of view. Approximate budget: Open, as long as the product pays for itself. Requires: Network management software. Concerns: Ease of management, the ability to measure response times and produce detailed reports. Winner: AppManager AppManager is the most suitable product here. It can be used to measure SLAs and would be ideal for a company needing to measure the performance of critical applications. It can also monitor a large number of applications running on Windows, Unix, and Linux-based systems. Originally we set out to review bandwidth monitoring products but two out of three the products submitted focused more on network and systems management, with bandwidth monitoring being a small component. The Lightspeed Systems product, however, is a pure bandwidth management tool, however it arrived at the Labs too late for us to properly test and compare it to the other products. For this reason we aren't awarding Editor's Choice in this review. Having said that, if you are looking for a product to only manage bandwidth, out of the products listed here you would be best off going with Lightspeed Systems -- it focuses on identifying users that use file sharing applications and also allows you to shape your bandwidth by giving priority bandwidth to specific applications.
When making a decision on which network and systems management tool is the most appropriate ask yourself whether you need a tool that just monitors your network, helps you troubleshoot network problems, or keeps an eye on system SLAs.
RMIT IT Test Labs is an independent testing institution based in Melbourne, Victoria, performing IT product testing for clients such as IBM, Coles-Myer, and a wide variety of government bodies. In the Labs' testing for T&B, they are in direct contact with the clients supplying products and the magazine is responsible for the full cost of the testing. The findings are the Labs' own -- only the specifications of the products to be tested are provided by the magazine. For more information on RMIT, please contact the Lab Manager, Steven Turvey.
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